Friend needs help with a tourist visa to come into Canada

my friend has been having issues with getting a tourist visa for his wife. They are both residing in China. He is a Canadian citizen and she is a Chinese citizen.

Here is his message to anyone able to assist in quotes.

Situation: - I am a Canadian citizen working and living in China - I have a wife who is Chinese - We have property, savings in China, with the intention to stay in China

What we want: - to obtain a tourist VISA for my wife so we can visit Canada where my parents live, together

Problem: We have applied for a tourist visa 3 times within the last three years, about a year apart, but have gotten rejections for all three attempts.

The last application's rejection notes from ATIP ONLY noted down Family and Financial ties to Canada seemed stronger than home country and travel purpose seemed unclear - no other financial, travel experiences, etc. reasons.

I feel that it is because of my Canadian Citizen status that is making the VO think she will overstay, but if I were not Canadian, with my parents there, she would have no reasons to visit Canada in the first place.

My question is:

What or how should I apply next time to address this? I feel that this reason is quite subjective. And we wrote a clear letter stating that we plan to live in China, and our purpose is to visit for about a week with dates specified.

on our second application, we didn't go too in depth about my plans in China; so when they said family ties, it was understandable, but the last one, we provided so much showing my intentions of staying in China and that we will only go back to visit - we have the spousal sponsorship route, so why would we do something illegal?

We are not considering sponsorship at this moment because we fear that if we get the green card and let it expire (not go back or stay in Canada), they might not give us another pass when we really do want to go back.

This is my first time on the forum, so if I made any mistakes, please forgive me. I am truly at blank with this problem because I have contacted VISA agencies and they don't really know, and getting a lawyer is too expensive without a clear go ahead.

Thanks again for your help!